Desining Promotion in warehouse

[Z_K]

We are bringing Promotion data to warehouse.
1)we have Promotion (PromotionID,PromotionName,Validity)
2)we have PromotionCode (PromoCodeID,PromoCode)
3)PromoCodeID is associated with orders
4)one promotion can have n no. of PromoCodes associated with it , also one promoCode can be recycled to be associated with another promotion
4)There are millions of promocode

Promotion needs to be evaluated from different subject areas like Order,Billing

What design approach should we take
1)one PromotionDim and one PromoCodeDim and one Fact with PromotionID,PromotionCodeID
2)one PromotionDim and one PromoCodeDim and one Fact with PromotionID,PromotionCodeID,orderID
3)one PromotionDim and one Fact with PromotionID,PromotionCodeID,orderID

any other option we can go with.
Any help/suggestion is much appreciated